In situ laser annealing as pathway for the metal free synthesis of tailored nanographenes
authors Milotti, V; Melle-Franco, M; Steiner, AK; Verbitskii, I; Amsharov, K; Pichler, T
nationality International
journal NANOSCALE ADVANCES
keywords ON-SURFACE SYNTHESIS; F BOND ACTIVATION; GRAPHENE NANORIBBONS; BAND-GAP; TEMPERATURE
abstract Tailored synthesis of nanographenes, and especially graphene nanoribbons (GNR), has been achieved on metal substrates via a bottom-up approach from organic precursors, which paves the way to their application in nanoelectronics and optoelectronics. Since quantum confinement in nanographenes leads to the creation of peculiar band structures, strongly influenced by their topological characteristics, it is important to be able to exactly engineer them in order to precisely tune their electronic, optical and magnetic properties. However practical application of these materials requires post-synthesis transfer to insulating substrates. Recently, cyclodehydrofluorination of fluorinated organic precursors has been shown to be a promising pathway to achieve metal-free bottom-up synthesis of nanographenes. Here we present how to apply in situ laser annealing to induce cyclodehydrofluorination leading to nanographene formation directly on non-metallic surfaces. In this work, we analyze the changes in the Raman fingerprint of the fluorinated precursor tetrafluoro-diphenyl-quinquephenyl (TDQ) during the laser annealing process in high vacuum (HV), demonstrating that both heating and photo-induced processes influence the cyclization process. Hence, in situ laser annealing allows not only to influence chemical reactions, but also to have a fast and contact-free monitoring of the reaction products. Optimization of the laser annealing process adds a new level of control in the tailored synthesis of nanographenes on non-metallic substrates. This is a very promising pathway to unravel the full application potential of nanographenes in general and GNR in particular, enabling a fast optimization of precursor molecules and substrate geometry engineered for specific applications.
publisher ROYAL SOC CHEMISTRY
issn 2516-0230
year published 2021
volume 3
issue 3
beginning page 703
ending page 709
digital object identifier (doi) 10.1039/d0na00909a
web of science category 7
subject category Chemistry, Multidisciplinary; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary
unique article identifier WOS:000616675500007

Sponsors

1suponsers_list_ciceco.jpg